BBC Earth

Episode 3 – Mammals

Preview

Fly among one of the largest migrations on Earth, as more than 10 million fruit bats leave the Congo basin and converge in a few special trees in Zambia to feed. Sprint with the tiny, extraordinary-looking sengis as it escapes a predatory lizard, see 30 polar bears gather to feed on a bowhead whale carcass and witness the biggest fight on Earth – male humpback whales battling for a female.

Preview next episode.